Design of Nanostructured Waterborne Adhesives with Improved Shear Resistance

The mechanical and adhesive properties of a series of model nanostructured waterborne PSA films have been characterized. The base polymer composition of the latex has been kept constant but systematic modifications have been carried out: the introduction of nanoparticles localized at the interfaces between particles, and the incorporation of a crosslinking agent. The mechanical properties have been characterized and show that the most effective modifications result in an increase in the low-frequency modulus in the small-strain regime and in a more pronounced softening and strain-rate-dependent behavior in the large-strain regime. In industrial standard tests, this combination gives a dramatically increased resistance to shear while maintaining a high value of peel resistance.